How can the carbon stored in plants reach the atmosphere?

Evaporation
Diffusion
Photosynthesis
Cellular Respiration

Cellular Respiration

Explanation:

Chemical energy in plants is typically stored within the bonds of glucose molecules. These are broken down during respiration, in a process that generates the energy molecules, ATP. Glucose is converted to pyruvate in the cytoplasm; then,  in the mitochondria, this process uses O2 for ATP generation in the Citric acid cycle, along with oxidative phosphorylation. Carbon dioxide is produced along with water and molecules of ATP.

overall: C6H12O6 (glucose) + 6 O2 → 6 CO2 + 6 H2O + ≈38 ATP

the answer to your question is b

c is the answer : )               your welcome